Buffer



Sept. 7, 1965 l.. T.'| A BELLE BUFFER 'Filed Nov. 7, 1963 INVENTOR.

L dure/7c BY United States Patent O 3,204,731 BUFFER Laurence T. La Belle, Westchester, Ill., assignor to W. H. Miner, Inc., Chicago, Ill., a corporation of Delaware Filed Nov. 7, 1963, Ser. No. 322,097 6 Claims. (Cl. 213-221) The present invention relates to a shock absorber and, more particularly, to a buffer device for use on railroad cars to cushion and absorb forces developed as a result of relative movement of the cars toward each other.

It is an impo-rtant object of the present invention to provide a new and improved buffer device which is relatively inexpensive to manufacture and which is therefore particularly well adapted for use as a transition butler during a conversion from railroad cars having drawbar hook-type couplers to cars having automatic couplers, this buffer device bein-g adapted to provide protection be- -tween any combination of such cars.

Another important object of the present invention is to provide la new and improved buffer device which is characterized 'by a pair of telescopically assembled tubular members one of wh-ich has a buffer cap at one end thereof and the other of which has a mounting plate at the opposite end thereof and by one or more elastomeric cushioning pads and a coil spring arranged in series relationship between the buffer cap and the mounting plate for normally biasing the tubular members into their maximum extended condition.

Still another object of the present invention is to provide a new and improved buffer device of the character described wherein a follower plate is provided between the elastomeric cushioning pads yand the coil spring with the follower plate being engageable with an interior shoulder on one of the tubular members in a manner such that the elastomeric pad or pads are normally partially precompressed and with a cylindrical guide portion being provided on the follower plate for engagement by the 'buffer cap prior to full closure of t-he buffer device.

Another important object of the present invention iS to provide a new and improved buffer device of the character described wherein the outer tubular member is provided with a pair of diametrically opposite longitudinally extending outwardly disposed groove-like offset portions, wherein the inner tubular member is provided with a pair of d-iametrically opposite outwardly directed lugs which are complementary to and are received in the foregoing groove-like odset portions, and wherein elongated keys extend transversely through the offset portions of the outer member and are engageable by the lugs on the inner member to determine the maximum extension of the buffer device.

A still fur-ther object of the present invention is to provide a new and improved butler device of the character described wherein the keys -are retained in the odset portions of the outer tubular member as a result of engagement by the leading ends thereof with lugs or small tabutrnents provided on the outer surface of the outer tubular member and by the depositing of small quantities of weld material between the trailing ends of the keys and the outer `surface of the outer tubular member after assembly of the keys in the offset portions thereof.

Certain other objects of the invention will, in part, be obvious and will in part appear hereinafter.

yFor a 4more complete understanding of the nature and scope of the invention reference may now be had to the accompanying drawings wherein:

FIGURE l is a composite View of a butler device embodying a preferred form of the invention taken generally on the line 1-1 of FIGURE 2 with the portion above the cen-ter line being a central vertical section and the portion below being a central horizontal section;

3,204,731 Patented Sept. 7, 1965 ICC FIGURE 2 is a vertical section taken generally along the line 2-2 of FIGURE l with the lower portion of the mounting plate broken away;

FIGURE 3 is a rear end elevational view looking toward the right end of the buffer device as shown in FIG- URE l with the upper and lower portions of the mounting plate broken away;

FIGURE 4 is a rear end elevational view of the removable end wall portion of the mounting plate;

FIGURE 5 is a vertical sectional view taken gene-rally along the line 5-5 `of FIGURE 1 with side portions of the buffer cap broken away; and

FIGURE 6 is a fragmentary central section of a moditied buffer device embodying the invention and having pinand-slot mean-s for determining the maximum extension of the device.

As best illustrated in FIGURE l, a butler device 10 embodying one form of the invention includes an outer tubular member 11 having a mounting plate 12 formed integrally on one end thereof for attaching the device 10 to the end of a railroad car and an inner tubular member 13 having one end telescopically assembled in the op- 'posite open end of the tubular member 11 and having a conventional buffer cap or head 14 integrally formed on the opposite end thereof. As will be described hereinafter, resilient means are provided for biasing the inner tubular member 13 outwardly of the outer tubular member 11 as well as stop means for determining the maximum extension of the inner tubular member 13 and for preventing disassembly of the device 10.

The mounting plate 12 is character-ized by a central generally circular opening 15 which is co-axial with the tubular portion of the member 11 and which is normally closed by a Iconventional general-ly circular removable end wall 16. As best illustrated in FIGURES 1, 3 and 4, the mounting plate opening 15 is characterized by a pair of diametrically opposite upper and lower inwardly directed danges 17 each of which has an .arcuate length of approximately and the inner face of the removable end wall 16 is characterized by a pair of diametrically opposite outwardly directed flanges 18 each of which has an arcuate length of approximately 90. The end wall 16 is assembled in the mounting plate 12 in an -obvious manner by positioning same with the flanges 18 at the sides thereof, inserting the end wall 16 through the opening 15, and rotating same approximately 90 to engage the wall flanges 1S behind the opening flanges 17, as shown in FIGURE 3.

The mounting plate opening 1S extends inwardly of the tubular member 11 for a distance which is approxirnately equal to one-quarter of the length thereof whereby to define a cylindrical chamber 19 having a diameter somewhat greater than the inner diameter of the remaining portion of the length of the tubular member 11, with a shoulder 20 directed toward the removable end wall 15 being defined therebetween. The major portion of the outer tubular member 11 dened between the shoulder 20 and the open end thereof is reduced in outer diameter tand is characterized by a pair of diametrically opposite longitudinally extending outwardly disposed groove-like offset portions 22 which are centered in a horizontal plane passing through the longitudinal axis of the tubular member 11. As best illustrated in FIGURE 2, both the inner land outer surfaces of this portion of the outer tubular inem-ber 111 have thi-s outwardly offset configuration. The groove-like offset portions 22 extend into the chamber 19 and thus form a pair of diametrically opposite gaps 23 (FIGURE 5) in the shoulder 20.

The inner end of the inner tubular member 13 is provided with a pair of diametrically opposite outwardly directed lugs or ilanges 25 which are complementary to and are received in the pair of groove-like offset portions 22 of the outer tubular member 11 whereby to provide longitudinal guiding for the inner tubular member 13 during longitudinal movement thereof relative to the outer tubular member 11 and also to prevent rotational movement of the inner tubular member l13 relative to the outer tubular member 1'1.

To determine the maximum extension of the buffer device shown in FIGURES 1-5 and described thus far herein and to prevent disassembly thereof, a pair of transversely aligned slots 27 are provided in the side or leg portions of each of the offset portions 22 of the outer tubular member 11 ltoward the open end thereof with an elongated key member 28 extending transversely therethrough in a manner such that the key members 28 extend through the grooves Z2 and are engageable by the lugs 25 on the inner tubular member 13 which are slidably disposed in the groove-like offset portions 22 of the outer tubular member 11. In assembling the buffer device 10, the key members 28 are inserted through the slots 27 after the inner tubular member 13 has 'been telescopically inserted into the outer tubular member 11 with the lugs 25 moved inwardly past the slots 27. The key members 28, which are disposed at right angles to the longitudinal axis of the member 11, are retained in the slots 27 by having the leading ends thereof abut against small lugs or abutments 29 (FIGURE 2) provided on the outer surface of the tubular member 11 and by depositing small quantities of weld material between the trailing ends of the key members 28 and the outer surface of the tubular member 11, as indicated at 30 in FIGURE 2.

The resilient means for normally biasing the buffer device 10 into its maximum extended condition includes at least one cushioning pad 32 and a coil spring 33 which are arranged in series relationship between the buffer cap 14 and the mounting plate 12. The pad 32, which is disposed in the chamber 19 and is seated against the inner surface of the removable end wall 16, is of a conventional type and is characterized by a peripherally dished elastomeric pad 34 and by a pair of rigid lsupport elements 35 bonded to opposite force-receiving faces thereof.

A follower member or plate 38 is provided between the elastomeric cushioning pad 32 and the coil spring 33 with the follower member being seated against the shoulder 20. The dimensions are such that the elastomeric pad 32 is normally partially precompressed to provide more effect-ive cushioning characteristics. To facilitate assembly of the follower member 38, which vhas an outer diameter slightly less thanfthat of the chamber 19, through the end wall opening 15, the follower member 38 is provided with a pair of diametrically opposite cut-away peripheral portions 39 each of which has an arcuate length of approximately 90 whereby to permit insertion of the follower member 38 past the opening lianges 17 and into abutting engagement with the'shoulder 20.

The face of the follower member 38 which abuts the shoulder 20 is provided with an integral centrally positioned tubular guide portion 41 which projects toward the buffer cap 14 with the projecting end thereof being disposed between the buffer cap 14 and the open end of the outer tubular member 11. The tubular guide portion 41 of the follower member 38 is spaced inwardly of the inner tubular member 13 to provide space for the coil spring 33 which is seated longitudinally between the buffer cap 14 and the follower member 38.

The buffer device 10 may be assembled by first 'telescopically assembling the inner and outer tubular members 11 and 13 and then securing the key members 2S in the slots 27 in the manner previously set forth herein. The coil spring 33, the follower member 38, and the elastomeric pad 32 may then be inserted, in proper se-V quence, through the mounting plate opening 15 after which the end wall 16 may be properly assembled in the mounting plate opening 15 in the manner previously' described. Suitable compression tools may be used in this assembly operation.

In operation, when buif forces are applied to the buffer cap 14, initial resistance to closure is normally provided solely by the coil spring 33. After the buffer cap 14 engages the end of the tubular guide portion 41 of the follower member 38, the coil spring 33 may be compressed no further and continued inward movement of the buffer cap 14, until same engages the -open end of the outer tubular member 11 at full closure, is resisted by further compression of the partially `precompressed elastomeric pad 32. Normally, the 'resistance to 'closurel of the buffer device '10 increases with inward `movement of the buffer cap 14.

There is illustrated in FIGURE`6 a fragmentary view of a buffer device 10a `having a modied form of stop and guide means for guiding the movement of the Abuffer Cap and for determining the maximum extension of the buffer device 10a. The device 10a includes an outer tubular member 11a, an inner tubular member 13a, a follower member (not shown) having a tubular guide portion 41a, and a coil spring 33a. Although not shown in FIGURE 6, the buffer device 10a `is similar to the buffer device 10 in that it also includes elements corresponding to the buffer cap 14, the mounting plate 15, the removable end wall 16, the follower member 38, the shoulder 20, and the elastomeric pad 32 of the device 10.

However, instead of the groove-like offset portions 22, the lugs -25 and the key members 28 of the device v10, the buffer device 10a is characterized by a pair of diametrically opposite longitudinally Kextending, slots 44 which are formed in the inner tubular member 13a and by a pair of diametrically opposite radially disposed guide pins or bolts 46 which are mounted -in the outer Atubular member 11a and which extend inwardly into guiding engagement in the slots 44. The guide pins46 guide the inner tubular member 13a during vlongitudinal movement thereof relative to the outer tubular member 11a and also prevent relative rotatable movement therebetween. Maximum extension of the buffer 'device 10a is vdetermined by engagement of the guide pins 46 with the ends o'f the slots 44 nearest the inner end of the inner tubular member 13a, as illustrated in FIGURE 6. Operationwise, the buffer device 10a cushions buff forces in the same manner as that described herein for the buffer device 10.

It will vrbe understood that certain additional changes and modifications may be made in the construction or arrangement of the buffer devices disclosed herein without departing from the spirit and scope of the invention as defined in the appended claims.

What is claimed as new is:

1. A buffer device comprising, a vpair of telescopically assembled tubular members having a buffer cap mounted on one of said members and a mounting plate mounted on the other at opposite ends of said assembly, elastomeric pad means and coil spring means arranged in series relationship between said buffer cap `and said mounting plate for normally biasing said pair of tubular members into an extended condition, the outer tubular member being characterized by a pair of diametrically opposite longitudinally extending outwardly disposed groove-like offset portions, a pair of diametrically opposite outwardly directed lugsformed on the inner tubular member at the inner end thereof, which lugs are complementary to and are received in Asaid groove-like offset portions, and a pair of elongated key members which extend transversely through .slots'formed in said offset portions at right angles to the longitudinal axis of said tubular members "and which are englageable by said lugs on said 'inner tubular member to determine the maximum extended 'condition of said tubular members.

2. A buffer device as recited in claim 1 wherein one end of each of said key members abuts one of a pair of lug formations formed on the outer surface of said outer tubular member, said key members being retained in said slots by a small quantity of weld material which is deposited between the opposite ends of said key members and the outer surface of said outer tubular member after assembly of said key members in said slots.

3. A buffer device comprising, a pair of telescopically assembled tubular members having a buffer cap mounted on one of said members and a mounting plate mounted on the other at opposite ends of said assembly, one or more elastomeric pads and a coil spring arranged in series relationship between said buffer cap and said mounting plate for normally biasing said pair of tubular members into an extended condition, a follower plate disposed between said elastomeric pads and said coil spring and having a cylindrical guide portion extending inwardly of said coil spring, said outer tubular member being characterized by a pair of diametrically opposite longitudinally extending outwardly disposed groove-like offset portions, a pair of diametrically opposite outwardly directed lugs formed on the inner end of said inner tubular member, which lugs are complementary to and are received in said groove-like offset portions, a pair of elongated key members which extend transversely through slots formed in said oifset portions at right angles to the longitudinal axis of said tubular members, which key members are engageable by said lugs on said inner tubular member to determine the maximum extended condition of said assembly, and a pair of lug formations formed on the outer surface of said outer tubular member for abutment by the leading ends of said key members when same are inserted through said slots in said offset portions thereof with said key members being retained in abutting engagement with said lug formations by small quantities of weld material which are deposited between the opposite trailing ends of said key members and the outer surface of said outer tubular member after assembly of said key members in said slots.

4. A buffer device comprising, in combination, a pair of telescopically assembled tubular members having a butfer cap mounted on one of said members and a mounting plate mounted on the other at opposite ends of said assembly, elastomeric pad means and coil spring means arranged in series relationship between said buffer cap and said mounting plate for normally biasing said pair of tubular members into an extended condition, a follower plate disposed between said elastomeric pad means and said coil spring means, shoulder means disposed on the inner Surface of the inner one of said tubular members and engageable by said follower plate in a manner such that said elastomeric pad means is normally in a partially precompressed state, the outer one of said tubular members being characterized by a pair of diametrically opposite longitudinally extending outwardly disposed groovelike offset portions, a pair of diametrically opposite outwardly directed lugs formed on the inner tubular member at the inner end thereof, which lugs are complementary to and are received in said groove-like offset portions, a pair of elongated key members which extend transversely through slots formed in said offset portions at right angles to the longitudinal axes of said tubular members and which are engageable by said lugs on said inner tubular member to determine the maximum extended condition of said tubular members, and means for retaining said key members in said slots.

5. A buffer device comprising, in combination, a pair of telescopically assembled tubular members having a buffer cap motmted on one of said members and a mounting plate mounted on the other at opposite ends of said assembly, resilient means disposed between said buffer cap and said mounting plate for normally biasing said pair of tubular members into an extended condition, the outer one of said tubular members being characterized by a pair of diametrically opposite longitudinally extending outwardly disposed groove-like oifset portions, a pair of diametrically opposite outwardly directed lugs formed on the inner tubular member at the inner end thereof, which lugs are complementary to and are received in said groove-like offset portions, a pair of elongated key members which extend transversely through slots formed in said offset portions at right angles to the longitudinal axes of said tubular members and which are engageable by said lugs on said inner tubular member to determine the maximum extended condition of said tubular members, and a pair of lug formations formed on the outer surface of said outer tubular member for abutment by the leading ends of said key members when same are inserted through said slots in said olset portions thereof with said key members being retained in .abutting engagement with said lug formations by small quantities of weld material which are deposited between the opposite trailing ends of said key members and the outer surface of said outer tubular member after assembly of said key members in said slots.

6. A buier device comprising, in combination, a pair of telescopically assembled tubular members having a buffer cap mounted on the inner one of said members and a mounting plate mounted on the outer one of said members at opposite ends of said assembly, elastomeric pad means and coil spring means arranged in series relationship between said buffer cap and said mounting plate for normally biasing said pair of tubular members into an extended condition with said elastomeric pad means being disposed against the inner surface of said mounting plate, a follower plate disposed between said elastomeric pad means and said coil spring means and having a cylindrical guide portion extending inwardly of said coil spring and terminating between said buffer cap and the end of said outer tubular member, whereby the end of said guide portion is engageable by said buer cap prior to engagement of the outer tubular member by said buffer cap at full closure of said buffer device, the outer one of said tubular members being characterized by a pair of diametrically opposite longitudinally extending outwardly disposed groove-like offset portions, a pair of diametrically lopposite outwardly directed lugs formed on the inner tubular member at the inner end thereof, which lugs are complementary to and are received in said groove-like oifset portions, and means associated with said outer tubular member and engageable by said lugs on said inner tubular member to determine the maximum extended condition of said tubular members.

References Cited by the Examiner UNITED STATES PATENTS 2,598,762 1/53 Dath 213-40 2,624,471 1/ 5 3 Lunde 213-221 2,930,491 3/60 Cook 213-221 FOREIGN PATENTS 743,558 10/ 32 France. 743,739 10/ 32 France.

MILTON BUCHLER, Primary Examiner.

LEO QUACKENBUSH, Examiner. 

6. A BUFFER DEVICE COMPRISING, IN COMBINATION, A PAIR OF TELESCOPICALLY ASSEMBLED TUBULAR MEMBERS HAVING A BUFFER CAP MOUNTED ON THE INNER ONE OF SAID MEMBERS AND A MOUNTING ON THE INNER ONE OF SAID MEMBERS MEMBERS AT OPPOSITE ENDS OF SAID ASSEMBLY, ELASTOMERIC PAD MEANS AND COIL SPRING MEANS ARRANGED IN SERIES RELATIONSHIP BETWEEN SAID BUFFER CAP AND SAID MOUNTING PLATE FOR NORMALLY BIASING SAID PAIR OF TUBULAR MEMBERS INTO AN EXTENDED CONDITION WITH SAID ELASTOMERIC PAD MEANS BEING DISPOSED AGAINST THE INNER SURFACE OF SAID MOUNTING PLATE, A FOLLOWER PLATE DISPOSED BETWEEN SAID ELASTOMETIC PAD MEANS AND SAID COIL SPRING MEANS AND HAVING A CYLINDRICAL GUIDE PORTION EXTENDING INWARDLY OF SAID COIL SPRING AND TERMINATING BETWEEN SAID BUFFER CAP AND THE END OF SAID OUTER TUBULAR MEMBER, WHEREBY THE END OF SAID GUIDE PORTION IS ENGAGABLE BY SAID BUFFER CAP PRIOR TO ENGAGEMENT OF THE OUTER TUBULAR MEMBER BY SAID BUFFER CAP AT FULL CLOSURE OF SAID BUFFER DEVICE, THE OUTER ONE OF SAID TUBULAR MEMBERS BEING CHARASTERIZED BY A PAIR OF DIAMETRICALLY OPPOSITE LONGITUDINALLY EXTENDING OUTWARDLY DISPOSED GROOVE-LIKE OFFSET PORTIONS, A PAIR OF DIAMETRICALLY OPPOSITE OUTWARDLY DIRECTED LUGS FORMED ON THE INNER TUBULAR MEMBER AT THE INNER END THEREOF, WHICH LUGS ARE COMPLEMENTARY TO AND ARE RECEIVED IN SAID GROOVE-LIKE OFFSET PORTIONS, AND MEANS ASSOCIATED WITH SAID OUTER TUBULAR MEMBER AND ENGAGABLE BY SAID LUGS ON SAID INNER TUBULAR MEMBER TO DETERMINE THE MAXIMUM EXTENDED CONDITION OF SAID TUBULAR MEMBERS. 